Wireless radio frequency communications has enabled truly mobile telecommunication service and extended communication service into areas that may otherwise be difficult to reach with conventional wire line based telecommunications infrastructure. For instance, various forms of mobile wireless communications such as CDMA, GSM, TDMA have proliferated worldwide in the last decade. Further, fixed location wireless services promise to economically bring telecommunications to areas of the world where the cost of installing a wire-based telecommunication switching infrastructure would be prohibitively high.
Certain geographic service areas, however, present a challenge for providing wireless service. Electromagnetic signals propagating at the radio frequencies (“RF”) typically used for wireless communications have difficulty penetrating obstacles such as mountains, valleys, buildings, or simply long distances. Other forms of interference may make providing reliable wireless services a challenge. The interior of buildings and other areas near tall buildings and earthen obstacles may be difficult to reach with service or have dead spots within the coverage area.
Fiber optic links can be used to extend wireless communication service into areas which would be difficult for wireless signals to reach. Transmitting RF over fiber allows radio signals used for wireless communications to be carried to wireless access points which can be placed in areas that would otherwise be difficult for wireless services to reach such as a campus of buildings, large parking structures, enclosed shopping malls, tunnels, underground transportation complexes, etc. Fiber provides high speed, high isolation and immunity to electrical interference, plus low loss for spanning distances without the need for repeaters, amplifiers or other costly equipment. By transmitting RF signal over a fiber optic link, wireless signals can be economically extended into areas without the cost of installing conventional wire-based telecommunications switching infrastructure.
The RF-to-fiber interface is also easily provided with low cost equipment and fiber provides high bandwidth and transmission capacity. RF over fiber extender links or loops are typically interfaced directly with conventional wireless base stations (BS) providing wireless service, further leveraging existing infrastructure and reducing the cost of providing service.
Relying on existing wireless base stations to interface fiber links, however, may not be an efficient manner of handling calls on a fiber link. For instance, using the fiber link to simply extend the wireless network requires the conventional wireless base stations to still process all call traffic from the fiber extender link. Even local call traffic initiated from and terminated between stations entirely within the same extender loop is connected through the wireless base station, even though the call does not need to be connected through the base station. Such call routing raises issues with network capacity and equipment costs.
By providing equipment capable of switching wireless calls on the fiber link, efficiencies in call processing may be realized. Thus, there is a need to better provide equipment capable of processing and handling calls transported on fiber links.